Description of Ditylenchus paraparvus n. sp. from Iran with an updated list of Ditylenchus Filipjev, 1936 (Nematoda: Anguinidae).

During a survey, 12 known and one new species of Ditylenchus Filipjev, 1936 were collected from southern provinces of Iran during 2013-2017. Ditylenchus paraparvus n. sp. is characterised by a short body length (441-543 µm), lateral field with four lines, delicate and short stylet (6-7.5 µm) with small rounded or posteriorly sloping knobs, pyriform and offset basal pharyngeal bulb, V = 67.7-76.4, short post-vulval uterine sac less than one vulval body width long, small spicules (12.5-15 µm) and almost cylindrical tail (71-90 µm) with rounded end. Morphometric data of studied species are presented and intraspecific variation of their morphometrics and morphological characters is discussed. The list of the world Ditylenchus species is updated, and a dichotomous identification key and an updated tabular compendium for 63 valid species is provided.